Integrated acid regeneration of ion exchange resins for industrial applications

ABSTRACT

Methods and systems for an integrated acid regeneration of ion exchange resins are disclosed for use in cleaning applications. Acid resins designed for use in a variety of cleaning application using a treated, softened, acidic water source are disclosed. Various methods of using the softened acidic water generated by acid regenerate-able ion exchange resins within a cleaning application, e.g. ware wash machine, are disclosed to beneficially reduce spotting, filming and scale buildup on treated surfaces, reduce and/or eliminate the need for polymers, threshold reagents and/or rinse aids, and using protons generated in the acidic water effluent for triggering events useful in various cleaning applications.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional application of U.S. ProvisionalApplication No. 61/569,829, filed Dec. 13, 2011, which is hereinincorporated by reference in its entirety.

FIELD OF THE INVENTION

The invention relates to methods and integrated apparatuses for the acidregeneration of ion exchange resins for use in various industrialcleaning applications. In particular, an acid regenerated resin systemis integrated into a ware wash machine or other inline cleaning machinefor use in any cleaning application using a water source to provide asoftened acidic water source exhibiting relatively lower total dissolvedsolids (TDS). Various methods of using the softened acidic watergenerated by acid regenerate-able ion exchange resins are alsodisclosed. In addition, the methods and apparatuses according to theinvention are further beneficial in reducing spotting and filming ontreated surfaces, preventing scale buildup on treated surfaces, reducingpolymers and threshold reagents necessary in a detergent source, andusing protons generated in the acidic water effluent for triggeringevents useful in various cleaning applications as disclosed herein.

BACKGROUND OF THE INVENTION

Various water treatment methods for decreasing hardness of water areknown and commercially employed. Detergents and other cleaning agentsoften contain numerous components to improve the cleaning activity ofthe detergent, including for example, components to counteract theeffects of water hardness. Hard water is known to reduce cleaningefficacy both by forming films on surfaces and reacting with detergentand other cleaning components, making them less functional in thecleaning process. Various methods for counteracting and/or eliminatingwater hardness have been implemented by those skilled in the art,including for example, adding chelating agents or sequestrants intodetersive compositions in amounts sufficient to handle the hardness ionsand/or softening a water source via ion exchange. Ion exchange can beused to exchange hardness ions, such as calcium and magnesium, in thewater with sodium or other ions associated with a resin bed in a watersoftening unit.

Various ion exchange methods are known by those skilled in the art. Mostcommonly, water is run through an exchange resin to adhere the hardnessions calcium and magnesium to a resin in the softener. However, when theresin becomes saturated it is necessary to regenerate the resin usinglarge amounts of sodium chloride dissolved in water. This regenerationprocess has numerous known disadvantages, namely requiring the use ofbriny solutions and chloride from added sodium chloride used to flushout the resin. Accordingly, when water softeners regenerate they producea waste stream that contains significant amounts of sodium, creating aburden on the system, e.g., sewer system, in which they are disposed of.The generated waste presents a multitude of downstream water re-useconcerns, including for example water re-use applications like potablewater usage and agriculture. Further, traditional water softeners add tothe salt content in discharge surface waters, which has become anenvironmental issue in certain locations. These and other limitations ofcommercially-available water softening methods are described in furtherdetail in U.S. patent application Ser. No. 12/764,621, entitled “Methodsand Apparatus for Controlling Water Hardness,” the entire contents ofwhich are hereby expressly incorporated herein by reference.

Accordingly, it is an objective of the claimed invention to developimproved methods and integrated systems for regenerating ion exchangeresins for use in in-line institutional and industrial applications,such as ware wash machines.

A further object of the invention is to develop a system and methods forusing acid regenerate-able ion exchange resins to pre-treat water forthe various institutional and industrial applications, resulting in thereduced demand for polymers and threshold reagents in cleaningcompositions (e.g. detergents).

A further object of the invention is to improve ware wash resultsthrough the application of softened acidic water generated by integratedacid regenerate-able ion exchange resin systems.

A still further object of the invention is to develop methods forapplying protons in a treated water source to trigger events, such asregeneration of the resins, dispensing additional detergent and/or othercleaning aids, and the like within a ware wash machine or other inlinecleaning machine.

Still further, the invention sets forth methods and systems for reducingscale build-up in ware wash applications by treating a water sourceusing an acid regenerate-able ion exchange resin.

Still further, the invention provides methods and systems for using anacid regenerated ion exchange resin in ware wash applications to reduceTDS for improved ware washing, including reduced spotting and/or filmformation.

BRIEF SUMMARY OF THE INVENTION

In an aspect of the invention, an integrated system employing an ionexchange resin regenerated by an acid for producing an acidic softenedwater source comprises: an inlet for providing a water source; a watertreatment reservoir, wherein the inlet is in fluid communication withthe water treatment reservoir; a water treatment component housed withinthe water treatment reservoir, wherein said water treatment componentcomprises at least one ion exchange resin capable of generating atreated water source by exchanging protons on said resin for dissolvedcations including water hardness ions and total dissolved solids in saidwater source, and wherein said ion exchange resin is an acid form or inan inert metal form; an outlet, wherein the outlet is in fluidcommunication with the water treatment reservoir; a chamber into whicharticles are placed for cleaning; a treated water delivery line in fluidcommunication between the outlet and the chamber; a wash tank, whereinthe wash tank is in fluid communication with a dispensing module thatdispenses a wash agent into the wash tank; a wash agent delivery line influid communication with the wash tank and the chamber; an acid deliveryline in fluid communication with the water treatment reservoir, whereinan acid regenerant is delivered to the water treatment reservoir forregenerating the ion exchange resin. In an aspect, the treated watersource is a softened, acidic, and low total dissolved solids (TDS) waterhaving a hardness level of less than about 2 grains and a pH less thanabout 6.

In another aspect of the invention, a method for treating hard water foruse in a cleaning application using an acid regenerated ion exchangeresin comprises: contacting a hard water source for use in a ware washmachine with a water treatment composition, wherein the water treatmentcomposition comprises at least one ion exchange resin, wherein the ionexchange resin generates a treated water source by exchanging protons onsaid resin for dissolved cations including water hardness ions and totaldissolved solids in said water source, wherein said ion exchange resinis an acid form or in an inert metal form, and wherein said ion exchangeresin is regenerated using an acid; generating the treated water sourcewithin a ware wash machine; and providing the treated water source to achamber into which articles are placed for cleaning;

wherein the treated water source is a softened, acidic and low totaldissolved solids (TDS) water having a hardness level of less than about2 grains and a pH less than about 6.

While multiple embodiments are disclosed, still other embodiments of thepresent invention will become apparent to those skilled in the art fromthe following detailed description, which shows and describesillustrative embodiments of the invention. Accordingly, the drawings anddetailed description are to be regarded as illustrative in nature andnot restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1B show an embodiment of an apparatus that can be retrofittedto a system for use of an acid regenerating ion exchange resin invarious cleaning applications.

FIG. 2 shows an embodiment of the apparatus that uses an acid regenerantto regenerate an ion exchange resin according to the invention.

FIGS. 3A-3B show an embodiment of the invention using a layered ionexchange resin bed (3A) and a mixed layered ion exchange resin bed (3B)for treating a water source.

FIG. 4 shows an exemplary schematic for an integrated acid regeneratingion exchange resin apparatus in a ware wash system.

FIG. 5 shows an exemplary schematic for the regeneration of anintegrated acid regenerating ion exchange resin apparatus in a ware washsystem according to the invention.

FIG. 6 shows a diagram of the capacity of an acid regenerated ionexchange resin v. pH of treated water according to an embodiment of theinvention.

FIG. 7 shows a diagram of the capacity of an acid regenerated ionexchange resin v. water hardness of treated water according to anembodiment of the invention.

FIG. 8 shows a diagram of the capacity of a layered weak acid ionexchange resin bed (single type of resin) v. a layered weak acid ionexchange resin and strong acid ion exchange resin bed on treatment ofwater hardness.

FIG. 9 shows a diagram of the pH v. the capacity (gallons) of a layeredweak acid ion exchange resin bed (single type of resin) v. a layeredweak acid ion exchange resin and strong acid ion exchange resin bed.

FIGS. 10A-10B show diagrams of the pH achieved from the acid resinsresulting from the regeneration using a strong acid regenerant accordingto an embodiment of the invention.

FIG. 11 shows a diagram of the hardness of treated water after theregeneration of the resin employing the exemplary acid regenerants ofFIGS. 10A-10B according to an embodiment of the invention.

FIG. 12 shows a diagram of the pH of the resin employing varioussuitable acid regenerants according to embodiments of the invention.

FIG. 13 shows a diagram of the hardness of treated water after theregeneration of the resin employing the various suitable acidregenerants of FIG. 12 according to embodiments of the invention.

Various embodiments of the present invention will be described in detailwith reference to the drawings, wherein like reference numeralsrepresent like parts throughout the several views. Reference to variousembodiments does not limit the scope of the invention. Figuresrepresented herein are not limitations to the various embodimentsaccording to the invention and are presented for exemplary illustrationof the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure relates to methods and systems for usingintegrated acid regenerate-able ion exchange resins to pre-treat waterfor in-line cleaning systems, namely ware wash applications. The methodsand systems or apparatuses for obtaining and applying softened acidicwater in a ware wash application herein have many advantages overconventional water softening systems and/or apparatuses aimed atreducing water hardness. For example, the invention provides numerousunexpected downstream benefits, including for example, improving waterquality and ware wash results, reducing consumption of detergents, otherpolymers and/or cleaning components traditionally employed in ware washapplications using hard water, preventing scale buildup, spotting and/orfilming on treated surfaces. In addition, there are various advantagesof the methods, systems and apparatuses using integrated acid softenedwater generated according to the invention to initiate downstream eventsin a ware wash application or other in-line cleaning application,including for example the regeneration of the resin and/or dispensing ofadditional cleaning components in a ware wash machine.

The embodiments of this invention are not limited to particular methods,systems and apparatuses for obtaining and applying softened acidic waterin a ware wash machine, which can vary and are understood by skilledartisans. It is further to be understood that all terminology usedherein is for the purpose of describing particular embodiments only, andis not intended to be limiting in any manner or scope. For example, asused in this specification and the appended claims, the singular forms“a,” “an” and “the” can include plural referents unless the contentclearly indicates otherwise. Further, all units, prefixes, and symbolsmay be denoted in its SI accepted form. Numeric ranges recited withinthe specification are inclusive of the numbers defining the range andinclude each integer within the defined range.

DEFINITIONS

So that the present invention may be more readily understood, certainterms are first defined. Unless defined otherwise, all technical andscientific terms used herein have the same meaning as commonlyunderstood by one of ordinary skill in the art to which embodiments ofthe invention pertain. Many methods and materials similar, modified, orequivalent to those described herein can be used in the practice of theembodiments of the present invention without undue experimentation, thepreferred materials and methods are described herein. In describing andclaiming the embodiments of the present invention, the followingterminology will be used in accordance with the definitions set outbelow.

The term “about,” as used herein, refers to variation in the numericalquantity that can occur, for example, through typical measuring andliquid handling procedures used for making concentrates or use solutionsin the real world; through inadvertent error in these procedures;through differences in the manufacture, source, or purity of theingredients used to make the compositions or carry out the methods; andthe like. The term “about” also encompasses amounts that differ due todifferent equilibrium conditions for a composition resulting from aparticular initial mixture. Whether or not modified by the term “about”,the claims include equivalents to the quantities.

As used herein, the terms “builder,” “chelating agent,” and“sequestrant” refer to a compound that forms a complex (soluble or not)with water hardness ions (from the wash water, soil and substrates beingwashed) in a specific molar ratio. Chelating agents that can form awater soluble complex include sodium tripolyphosphate, EDTA, DTPA, NTA,citrate, and the like. Sequestrants that can form an insoluble complexinclude sodium triphosphate, zeolite A, and the like. As used herein,the terms “builder,” “chelating agent “and” sequestrant” are synonymous.

As used herein, the term “lacking an effective amount of chelating (orbuilder/sequestrant) agent” refers to a composition, mixture, oringredients that contains too little chelating agent, builder, orsequestrant to measurably affect the hardness of water.

The term “cleaning,” as used herein, means to perform or aid in soilremoval, bleaching, microbial population reduction, or combinationthereof.

As used herein, the term “disinfectant” refers to an agent that killsall vegetative cells including most recognized pathogenicmicroorganisms, using the procedure described in A.O.A.C. Use DilutionMethods, Official Methods of Analysis of the Association of OfficialAnalytical Chemists, paragraph 955.14 and applicable sections, 15thEdition, 1990 (EPA Guideline 91-2). As used herein, the term “high leveldisinfection” or “high level disinfectant” refers to a compound orcomposition that kills substantially all organisms, except high levelsof bacterial spores, and is effected with a chemical germicide clearedfor marketing as a sterilant by the Food and Drug Administration. Asused herein, the term “intermediate-level disinfection” or “intermediatelevel disinfectant” refers to a compound or composition that killsmycobacteria, most viruses, and bacteria with a chemical germicideregistered as a tuberculocide by the Environmental Protection Agency(EPA). As used herein, the term “low-level disinfection” or “low leveldisinfectant” refers to a compound or composition that kills someviruses and bacteria with a chemical germicide registered as a hospitaldisinfectant by the EPA.

As used herein, the term “microorganism” refers to any noncellular orunicellular (including colonial) organism. Microorganisms include allprokaryotes. Microorganisms include bacteria (including cyanobacteria),spores, lichens, fungi, protozoa, virinos, viroids, viruses, phages, andsome algae. As used herein, the term “microbe” is synonymous withmicroorganism.

As used herein, the term “sanitizer” refers to an agent that reduces thenumber of bacterial contaminants to safe levels as judged by publichealth requirements. In an embodiment, sanitizers for use in thisinvention will provide at least a 99.999% reduction (5-log orderreduction). These reductions can be evaluated using a procedure set outin Germicidal and Detergent Sanitizing Action of Disinfectants, OfficialMethods of Analysis of the Association of Official Analytical Chemists,paragraph 960.09 and applicable sections, 15th Edition, 1990 (EPAGuideline 91-2). According to this reference a sanitizer should providea 99.999% reduction (5-log order reduction) within 30 seconds at roomtemperature, 25+/−2° C., against several test organisms.

For the purpose of this patent application, successful microbialreduction is achieved when the microbial populations are reduced by atleast about 50%, or by significantly more than is achieved by a washwith water. Larger reductions in microbial population provide greaterlevels of protection.

Differentiation of antimicrobial “-cidal” or “-static” activity, thedefinitions which describe the degree of efficacy, and the officiallaboratory protocols for measuring this efficacy are considerations forunderstanding the relevance of antimicrobial agents and compositions.Antimicrobial compositions can affect two kinds of microbial celldamage. The first is a lethal, irreversible action resulting in completemicrobial cell destruction or incapacitation. The second type of celldamage is reversible, such that if the organism is rendered free of theagent, it can again multiply. The former is termed microbiocidal and thelater, microbistatic. A sanitizer and a disinfectant are, by definition,agents which provide antimicrobial or microbiocidal activity. Incontrast, a preservative is generally described as an inhibitor ormicrobistatic composition.

As used herein, the term “solubilized water hardness” or “waterhardness” refers to hardness minerals dissolved in ionic form in anaqueous system or source, i.e., Ca⁺⁺ and Mg⁺⁺. Solubilized waterhardness does not refer to hardness ions when they are in a precipitatedstate, i.e., when the solubility limit of the various compounds ofcalcium and magnesium in water is exceeded and those compoundsprecipitate as various salts such as, for example, calcium carbonate andmagnesium carbonate.

As used herein, the term “threshold agent” refers to a compound thatinhibits crystallization of water hardness ions from solution, but thatneed not form a specific complex with the water hardness ion. Thisdistinguishes a threshold agent from a chelating agent or sequestrant.Threshold agents include a polyacrylate, a polymethacrylate, anolefin/maleic copolymer, and the like.

As used herein, the term “ware” refers to items such as eating andcooking utensils, dishes, and other hard surfaces such as showers,sinks, toilets, bathtubs, countertops, windows, mirrors, transportationvehicles, and floors. Wares are often comprised of various types ofplastics including but are not limited to, polycarbonate polymers (PC),acrilonitrile-butadiene-styrene polymers (ABS), and polysulfone polymers(PS). Another exemplary plastic includes polyethylene terephthalate(PET).

As used herein, the term “warewashing” or “ware washing” refers towashing, cleaning, or rinsing ware. Ware also refers to items made ofplastic.

As used herein, the terms “water” or “water source,” refer to any sourceof water that can be used with the methods, systems and apparatuses ofthe present invention. Exemplary water sources suitable for use in thepresent invention include, but are not limited to, water from amunicipal water source, or private water system, e.g., a public watersupply or a well. The water can be city water, well water, watersupplied by a municipal water system, water supplied by a private watersystem, and/or water directly from the system or well. The water canalso include water from a used water reservoir, such as a recyclereservoir used for storage of recycled water, a storage tank, or anycombination thereof. In some embodiments, the water source is not anindustrial process water, e.g., water produced from a bitumen recoveryoperation. In other embodiments, the water source is not a waste waterstream.

As used herein, the term “water soluble” refers to a compound orcomposition that can be dissolved in water at a concentration of morethan 1 wt-%. As used herein, the terms “slightly soluble” or “slightlywater soluble” refer to a compound or composition that can be dissolvedin water only to a concentration of 0.1 to 1.0 wt-%. As used herein, theterm “substantially water insoluble” or “water insoluble” refers to acompound that can be dissolved in water only to a concentration of lessthan 0.1 wt-%. For example, magnesium oxide is considered to beinsoluble as it has a water solubility (wt-%) of about 0.00062 in coldwater, and about 0.00860 in hot water. Other insoluble compounds for usewith the methods of the present invention include, for example:magnesium hydroxide with a water solubility of 0.00090 in cold water and0.00400 in hot water; aragonite with a water solubility of 0.00153 incold water and 0.00190 in hot water; and calcite with a water solubilityof 0.00140 in cold water and 0.00180 in hot water.

The term “weight percent,” “wt-%,” “percent by weight,” “% by weight,”and variations thereof, as used herein, refer to the concentration of asubstance as the weight of that substance divided by the total weight ofthe composition and multiplied by 100. It is understood that, as usedhere, “percent,” “%,” and the like are intended to be synonymous with“weight percent,” “wt-%,” etc.

EMBODIMENTS OF THE INVENTION

According to an embodiment of the invention methods, systems andapparatuses provide for the use of acid regenerate-able ion exchangeresins to pre-treat water for cleaning applications. Preferably, resinshaving a polymer matrix with carboxylic acid functional groups are usedto capture water hardness ions and thereafter acids are used toregenerate the resin for re-use in generating a softened acidic watersource for use in a cleaning application. Surprisingly, the presentinvention provides for novel uses of the various effluent waters of themethods, systems and apparatuses of the invention. In particular,whereas the effluent from the regeneration step is put to a waste streamand/or the effluent water from a service cycle is acidic softened waterand may be used for washing or rinsing in a variety of cleaningapplications. While an understanding of the mechanism is not necessaryto practice the present invention and while the present invention is notlimited to any particular mechanism of action, it is contemplated that,in some embodiments the benefits afforded according to the inventionresult from the generation of protons from the exchange of waterhardness ions onto the resin.

According to a further embodiment of the invention, the methods, systemsand apparatuses provide novel mechanisms for monitoring water sources.As opposed to monitoring and/or measuring water hardness ions in a watersource, the use of conventional pH measurements can be used to triggervarious events in a cleaning application. For example, a pH measurement(i.e. caused by the increase in protons/acidic water) can be used totrigger the step of regenerating the resin of a water treatmentcomponent or apparatus, and/or varying the detergent consumption neededto wash or rinse a surface in a particular cleaning application.Alternatively, the pH of incoming hard water can be compared to thetreated acidic softened water, wherein the pH differential can be usedto monitor a working system.

The invention overcomes the shortfalls of commercially-available watersoftening methods by providing an improved method for regenerating aresin and providing cleaning benefits from the treated effluent of asystem, namely the protons contributing to cleaning efficacy in variouscleaning applications. In addition, the invention provides theunexpected benefits of requiring the use of reduced amounts of polymers,threshold agents/reagents and/or other components in detergentcompositions. In a further unexpected application, the inventionprovides for the elimination of a chemistry input into a cleaningapplication, such as acidic rinse aids.

One skilled in the art will ascertain additional benefits, uses and/orapplications based upon the disclosure of the methods and systems of thepresent invention disclosed herein. Such embodiments are incorporated inthe scope of the present invention.

Apparatuses and Systems for Water Treatment

In some embodiments the present invention relates to apparatuses and/orsystems integrating the acid regenerated ion exchange resin(s) disclosedherein for in-line use of the softened acidic water in a cleaningapplication. The apparatuses and/or systems are suitable for use incontrolling water hardness. In some aspects, the apparatuses and/orsystems of the present invention include a substantially water insolubleresin material. Preferably, apparatuses and/or systems of the presentinvention do not precipitate a substance out of the water (e.g. athreshold agent). Without being limited to a particular theory of theinvention, the apparatuses and/or systems result in the release ofprotons from the resin in exchange for binding water hardness ions ontothe resin, causing an alteration in pH (i.e. acidic softened water),namely a decrease in pH as a result of the generation of protons fromthe resin. More preferably, the apparatuses and/or systems do notincrease the total dissolved solids (TDS) of the water source treated.

In some aspects, the apparatuses and/or systems of the present inventioninclude a water treatment composition or water preparation system(herein after the terms are used synonymously) integrated into acleaning application, such as for example a ware wash machine. The watertreatment composition may be in a variety of physical forms. In oneembodiment the water treatment composition comprises an ion exchangeresin.

Ion Exchange Resins

The ion exchange resin according to the apparatuses and/or systems ofthe invention may be in a variety of physical forms, including forexample, a sheet, a bead, a membrane or the like. In some embodiments,the ion exchange resin is a substantially water insoluble resinmaterial. In some embodiments, the ion exchange resin is an acid cationexchange resin. As disclosed herein, a variety of resin materials may beused with the apparatuses of the present invention to treat a watersource by exchanging protons on the ion exchange resins for dissolvedcations including water hardness ions and total dissolved solids in thewater source.

In some embodiments, the resin material includes an acid cation exchangeresin. The acid cation exchange resin may include a weak acid cationexchange resin, a strong acid cation exchange resin, and/or combinationsthereof (often referred to as layered resin systems or beds, which mayfurther include layered mixed resin systems or beds, as one skilled inthe art appreciates).

In an embodiment the ion exchange resin is a strong acid exchange resinhaving a polystyrene matrix and sulfonic acid functional group. In anadditional embodiment, the ion exchange resin may have a polystyrenewith sulfonic acid functional group, polystyrene with sulfonic acidfunctional group and mixtures of thereof.

Weak acid cation exchange resins suitable for use in the presentinvention include, but are not limited to, a cross-linked acrylic acidwith carboxylic acid functional group, a cross-linked methacrylic acidwith carboxylic acid functional group, and mixtures thereof. In someembodiments, resin polymers have additional copolymers added. Thecopolymers include but are not limited to butadiene, ethylene,propylene, acrylonitrile, styrene, vinylidene chloride, vinyl chloride,and derivatives and mixtures thereof.

In a preferred embodiment the ion exchange resin is a weak acid exchangeresin having a polyacrylic copolymer matrix and a carboxylic acidfunctional group. Preferably the ion exchange resin has a surface withfunctional groups comprising carboxylic acids. Alternatively, the ionexchange resin has a surface comprising functional groups comprisingsulfonic acids.

In some embodiments, the resin material is an acrylic acid polymer thatprovides a polyacrylate material having a molecular weight of about 150to about 100,000 to the water source. In other embodiments, the resinmaterial provides a polyacrylate material having a relatively lowmolecular weight, such as a molecular weight less than about 20,000, tothe water source. Without being limited according to the invention, allranges of molecular weights recited are inclusive of the numbersdefining the range and include each integer within the defined range.

In some embodiments, the resin includes a weak acid cation exchangeresin having H+ ions attached to the active sites. In additionalembodiments, the resin includes a weak acid cation exchange resin havingcarboxylic acid functional groups attached to the active sites.

Various commercially available weak acid cation exchange resins areavailable, and include but are not limited to: Amberlite® IRC 76 (DowChemical Company); Dowex® MAC-3 (Dow Chemical Company); and a variety ofadditional resins. Additional description of suitable resin materialsand systems, including additional commercially available resins aredisclosed in U.S. patent application Ser. No. 12/764,621, entitled“Methods and Apparatus for Controlling Water Hardness,” the entirecontents of which are hereby expressly incorporated herein by reference.

An alternative embodiment of the invention is the use of an anionexchange resin. Without wishing to be bound to a particular theory ofthe invention, use of an anion exchange resin may provide benefitsthrough obtaining a softened alkaline water source.

As one skilled in the art will ascertain, the resin material may beprovided in any shape and size, including beads, rods, disks orcombinations of more than one shape. In some embodiments, the resinmaterial is selected from the group consisting of a gel type resinstructure, a macroporous type resin structure, and combinations thereof.Without wishing to be bound by any particular theory it is thought thatthe resin particle size may affect the ability of the resin material tocontrol water hardness. For example, in some embodiments, the resinmaterial may have a particle size of from about 0.5 mm to about 1.6 mm.In other embodiments, the resin material may have a particle size aslarge of 5.0 mm. The resin material may also include a mixture ofparticle sizes, viz. a mixture of large and small particles. Withoutbeing limited according to the invention, all ranges recited areinclusive of the numbers defining the range and include each integerwithin the defined range.

Additional factors that are thought to have an effect on the ability ofthe resin material to control water hardness include, but are notlimited to, the particle size distribution, the amount of cross linking,and the polymers used. In some embodiments, the cross-linked polymer(e.g. acrylic acid) is about 0.5% cross-linked to about 25%cross-linked. In other embodiments, the polymer is less than about 8%cross-linked, less than about 4% cross-linked, or less than about 2%cross-linked. Without being limited according to the invention, allranges recited are inclusive of the numbers defining the range andinclude each integer within the defined range.

In some embodiments, the ability of the resin material to control waterhardness is impacted by whether there is a narrow particle sizedistribution, e.g., a uniformity coefficient of 1.2 or less, or a wide(Gaussian) particle size distribution, e.g., a uniformity coefficient of1.5 to 1.9. Without being limited according to the invention, all rangesrecited are inclusive of the numbers defining the range and include eachinteger within the defined range.

Further, it is thought that the selectivity of the resin can be modifiedto tailor the resin to have an affinity for one ion over another. Forexample, the amount of cross linking and type of polymers included inthe resin are thought to impact the selectivity of the resin. Aselective affinity for particular ions over other ions may be beneficialin situations where a high affinity for certain ions, e.g., copper, maybe damaging, e.g., foul or poison, to the resin itself. The resinmaterial may bind cations by a variety of mechanisms including, but notlimited to, by ionic or electrostatic force.

Acid Regenerants

Acid regenerants suitable for use in the regeneration of the ionexchange resins according to the apparatuses and/or systems of theinvention are necessary to remove water hardness ions from the resins. Avariety of acid regenerants may be employed to provide protons to theresin to restore capacity to soften and acidify water in need oftreatment according to the invention. In an aspect, the regenerant is anacid. Exemplary acids according to the invention include hydrochloricacid, sulfuric acid, phosphoric acid, nitric acid, citric acid, aceticacid, methane sulfonic acid and methyl sulfonic acid. In some aspectsthe acid regenerant is a strong acid. In other aspects the acidregenerant is a weak acid. In an additional aspect, the acid regenerantmay be an inorganic and/or organic acid. In an additional aspect, theregenerant is an acid salt. Exemplary acid salts include urea sulfateand monosodium sulfuric acid. In a preferred aspect, the regenerant isurea sulfate.

In an aspect, the acid regenerant is housed in a storage reservoir in aconcentrated form that is commercially-available. Concentratespreferably have pH less than about 5, preferably less than about 2,preferably less than about 1, and more preferably less than about 0.Without being limited according to the invention, all pH ranges recitedare inclusive of the numbers defining the range and include each integerwithin the defined range. For example, concentrated urea sulfate havinga pH from about −3 to about 1 is employed as a concentrated acidregenerant for the ion exchange resins of the invention. Preferably, theacid regenerant is be diluted prior to passing over the ion exchangeresin. This allows for the use of concentrated acid regenerants, whichamong other benefits reduces the transportation burdens and costs. In anaspect, the dilution ratio of acid regenerant to diluent (e.g. water) isfrom about 1:1 to about 1:20, preferably from about 1:2 to about 1:20.Without being limited according to the invention, all dilution ratioranges recited are inclusive of the numbers defining the range andinclude each integer within the defined range.

In an aspect, the acid regenerant is in contact with the resin for aperiod of time from a few minutes to about 90 minutes, preferably fromabout one minute to about 60 minutes, and more preferably from about 5minutes to about 30 minutes.

In an aspect of the invention, the concentration of the acid regenerantused in the regeneration cycle will depend upon the type of acidregenerant employed. In some embodiments, the concentration of the acidused in a solution for providing the acid regenerant to the ion exchangeresin is from about 1% to about 20%, from about 2% to about 10%, orabout 5% to about 10% of access of acid for regeneration. Without beinglimited according to the invention, all ranges recited are inclusive ofthe numbers defining the range and include each integer within thedefined range. In addition, the amount of hardness in need of removalfrom the ion exchange resin will impact the amount of acid regenerantemployed for the regeneration step of the invention.

Exemplary Water Preparation Systems

The apparatuses and/or systems of the present invention may be housedwithin a variety of water preparation systems for in-line use in acleaning system, such as a ware wash machine to provide acidified watersources for cleaning and/or rinsing. An example of a water preparationsystem or apparatus 20 for use in the present invention is shown inFIGS. 1A-1B, which may comprise, consist of and/or consistentessentially of: an inlet 22 for providing a water source to a treatmentreservoir 26; a treatment reservoir including a water treatmentcomposition 28 (e.g. ion exchange resin) and the water source to betreated 29; an outlet 24 for providing treated acidic water 31 from thetreatment reservoir 26; and a treated water delivery line 30 forproviding the treated acid water for a particular application within thecleaning system 32, namely a ware wash system.

According to the various methods of the invention, the water source 29passes over the ion exchange resin 28, and water hardness cations fromthe water source 29 (e.g. calcium and magnesium ions) attach to the ionexchange resin 28, displacing protons into the treated water sourcecreating an acidic softened water 31.

The apparatuses and/or systems of the present invention are designed forregeneration using an acid regenerant. Once the ion exchange resin 28reaches a point of exhaustion (wherein the multivalent hardness cationsfrom the water source have loaded onto the resin such that insufficientor no further exchange of cations occurs), an acid regenerant is used toremove the multivalent hardness cations from the cation exchange resin.An exemplary embodiment of such regeneration is shown in FIG. 2, whereinthe water preparation system or apparatus 20 further comprises, consistsof and/or consists essentially of a housing or storage reservoir 42containing an acid source 44 and a delivery line 46 for providing theacid source 44 to the treatment reservoir 26. The delivery line 46connects the acid source 44 with a water source 47 to generate a moredilute acid source 48 to regenerate the ion exchange resin 28. Thediluted acid source 48 is then pumped into the treatment reservoir 26 topass over the ion exchange resin 28 and cause the displacement of waterhardness cations with the protons from the dilute acid source, therebyregenerating the exhausted ion exchange resin and generating a wastesource of water containing hardness ions 50 to be removed from the waterpreparation system or apparatus 20.

The regeneration of the ion exchange resins can be triggered by avariety of events, as set forth in the description of the invention. Inan embodiment, the concentrated acid source 44 from the storagereservoir 42 is combined with the water source due to atmosphericpressure within the system triggered by an event. Triggering events, asreferred to herein for the regeneration of the ion exchange resins caninclude, for example, scheduled regeneration cycles based upon eitherset amounts (i.e. threshold levels) of the following and/or measurementsand targeted amounts of the following, including for example, volume ofwater treated by an ion exchange resin, TDS levels in the treated waterand/or water source to be treated according to the invention, pH of thetreated water, number of cleaning events/cycles since the previousregeneration of the ion exchange resin, and the like

As depicted in FIG. 2, the regeneration step moves the liquids in theopposite direction through the inlets and outlets, 22 and 24respectively, as that described with respect to FIGS. 1A-1B when the ionexchange resin 28 is used to remove water hardness to generate thesoftened acidified water. Beneficially, this reduces the complexity ofthe water preparation system or apparatus 20 in minimizing the number ofinlets/outlets and delivery line. In an additional embodiment, the wasteproduct from the regeneration step (i.e. water containing hardness ions50) could be added to the water source 29 for subsequent treatmentaccording to the methods of the invention.

The apparatuses and/or systems of the present invention may furtheremploy layered resin beds and/or layered mixed resin beds, as shown inFIGS. 3A-3B, respectively. In an embodiment of the invention, a layeredresin bed includes more than one acid cation exchange resin. Forexample, as shown in FIG. 3A, the water preparation system or apparatus20 may comprise, consist of and/or consist essentially of: a first inlet22 for providing a water source to a first treatment reservoir 26(housing a first ion exchange resin 28); a first outlet 24 for providingthe treated acidic water from the first treatment reservoir 26 to asecond treatment reservoir 26; a second inlet 22 for providing thetreated water source to the second treatment reservoir 26 (housing thesecond ion exchange resin 28); and a second outlet for providing thetreated acidic water to a treated water delivery line 30. It is to beunderstood from the description of the invention that a plurality ofresin beds may be employed, e.g. more than two treatment reservoir 26and more than two ion exchange resins 28. As set forth with respect toFIG. 1B, various embodiments of the invention may be employed for thedelivery of the treated acid water within the cleaning application 32.

In a further embodiment, as shown in FIG. 3B, the water preparationsystem or apparatus 20 may include a layered mixed resin bed which maycomprise, consist of and/or consist essentially of: a first inlet 22 forproviding a water source to a first treatment reservoir 26 (housing afirst ion exchange resin 28); a first outlet 24 for providing thetreated acidic water from the first treatment reservoir 26 to a secondtreatment reservoir 26; a second inlet 22 for providing the treatedwater source to the second treatment reservoir 26 (housing the secondion exchange resin 28, wherein the second ion exchange resin is adifferent ion exchange resin from that housed in the first treatmentreservoir or wherein the second ion exchange resin contains more thanone type of ion exchange resin, one of which may be the same as the ionexchange resin housed in the first treatment reservoir); and a secondoutlet for providing the treated acidic water to a treated waterdelivery line 30.

The layered acid cation exchange resins depicted in FIGS. 3A-3B mayinclude combinations of weak acid cation exchange resins, strong acidcation exchange resins, and/or combinations of both weak acid cationexchange resins and strong acid cation exchange resins.

In some embodiments, the treated water delivery line 30 in incorporatedwithin a washing and/or cleaning system 32, such as a ware wash systemas shown in FIG. 4. An exemplary wash machine 32 is a “ware wash”machine that is used to clean various types of dishware and kitchenobjects, such as, without limitation, pots and pans used in restaurants,cafeterias and bakeries. Objects washed by the ware wash machine 32 arereferred to herein as “articles.” The articles are provided to the warewash machine 32 on article racks, which are placed within the washchamber 78 of a wash machine 32. These and other types of ware washmachines may be employed according to the invention.

In an exemplary embodiment, an integrated water preparation system orapparatus 20 may include an inlet 22 for providing a water source to atreatment reservoir 26 (housing an ion exchange resin 28), an outlet 24for providing the treated acidic water from the treatment reservoir 26to a water delivery line 30 for further use within the ware wash system32, namely within the wash chamber 78 of the system. As further shown inFIG. 4, the ware wash system 32 provides a plurality of delivery lines60, 62 for pumping fluids through separate lines within the systems.Additional delivery lines may be further included for pumping fluidsthroughout the systems, including into the system and leaving thesystem, such as delivery lines 92, 94, 96 which are further disclosed inFIG. 5. In addition, additional storage tanks may be incorporated into aparticular wash system, such as a water storage tank 82 (as shown inFIG. 5). As such the exemplary figures are non-limiting examples of warewash cleaning systems 32 according to the invention.

In the exemplary embodiment shown in FIG. 4, there are two deliverylines 60, 62 to provide, respectively, rinse fluids (namely the treatedacidic water 31 without or without additional rinse aids 64) and washfluids (namely detergent solutions 70) through a plurality of spray arms66, 68 within the wash chamber 78. The plurality of spray arms 66, 68distributes water (or other fluid) spray 80 within the wash chamber 78of the system. The delivery of spray fluids 80 is shown in FIG. 4 asdelivering a rinse fluid; however such spray fluids 80 may further bedelivered through the other spray arms within the wash chamber. Thespray arms may be operably mounted within the wash chamber by a numberof mechanisms (not shown), including for example, operably mounted to aspindle for rotation about the spindle axis. As shown in FIG. 4 thespray arms are driven by pressure; however other embodiments forcontrolling the spray arms 66, 68 of a cleaning system 32 may be furtheremployed and are included within the scope of the invention. Forexample, as shown in FIG. 5 the rinse arm of the system may becontrolled by a pump 84. Either designs are suitable for the cleaningsystems of the invention.

In an aspect, the wash fluids are comprised of water and a detergentand/or other polymer source 70 housed in a wash tank 72 within thesystem. Such a system may employ a wash pump 74 to deliver the detergentand/or other polymer solution 70 as a spray fluid 80 through the sprayarm 68 of the system (such spray not illustrated in FIG. 4). In anaspect, the ware wash system 32 may include the use of a booster heater76 for the delivery of heated acidified water 31 in the delivery linefor the rinse step of a cleaning application. Use of a booster heater 76(including in any sump or delivery line) is optional and a matter ofimplementation.

In an aspect, the ware wash system 32 may use joined delivery linesemploying pumps at points of inlet (e.g. actuated 3-way valve) to reducethe number of pumps that are required for an integrated system.Beneficially, this allows a single pump to be used to apply more onewater and/or chemistry source to the cleaning application 32. Forexample, the delivery of a rinse aid may employ an additional tankwithin a system; however, such a delivery line may employ a pump toshare an inlet into the spray arms with, for example, the treated acidicwater 31 according to the invention in order to minimize the number ofdelivery lines within the system.

In a further aspect, the ware wash system 32 may include the use of anadditional treatment reservoir 26 within the system. Still furtheraspects may include the use of an additional water treatment apparatus.The additional water treatment apparatus may include for example, acarbon filter, a reverse osmosis filter, water softener, etc. Thereafterthe treated water may again be provided as a source for a cleaningapplication, such as the use within a ware wash application 32. It isexpected that the water treated with the additional water treatmentapparatus is delivered by the water delivery line 30, 60 to the sprayarm of the system 66. One skilled in the art shall ascertain that one ormore additional water treatment apparatuses may be employed with thewater preparation system or apparatus 20 of the invention. In addition,the one or more additional water treatment apparatuses may be employedbefore or after the water source is treated according to the methods ofthe invention with the water preparation system or apparatus 20. Assuch, the configuration of the water preparation system or apparatus 20treating a water source with the ion exchange resin 28 prior to use ofthe additional water treatment apparatus is a non-limiting embodiment ofthe invention. In a still further alternative embodiment, no additionalwater treatment apparatuses are employed with the water preparationsystem or apparatus 20 of the invention.

In aspects of the invention, the one or more tanks within a cleaningapplication can be optimized for that particular fluid (e.g. treatedacid water, detergent solution, rinse solution, etc.) by use of variouspumps, tanks, and nozzle selection.

In some embodiments, the incorporation of an integrated waterpreparation system or apparatus 20 (including a treatment reservoir 26housing an ion exchange resin 28) into a washing and/or cleaning system32 may employ additional tanks and fluid delivery lines for theregeneration of the ion exchange resin 28 according to the methods ofthe invention. As shown in a non-limiting embodiment in FIG. 5, theintegrated water preparation system or apparatus 20 for the depictedware wash cleaning system 32 further employs a recirculating method forregenerating the ion exchange resin. As a result, additional deliverylines, input lines and pumps are employed for such cleaning system.

A system employing a recirculating method for regenerating the ionexchange resin further includes a water storage tank 82 and rinse pump84 as a component of the cleaning system 32. A water storage tank 82 mayvary in shape, size, and/or orientation within the cleaning system 32. Awater storage tank 82 is useful for having treated water 31 readilyavailable within a cleaning system 32 for use. As depicted, a treatedwater source is transported via delivery lines 30, 60 directly to thewater storage tank 82. However, in alternative embodiments the waterdelivery line 30 may directly transport the treated water to the waterstorage tank 82. In still other embodiments the water delivery line(s)30 and/or 62 may directly transport the treated water to either one orboth of the spray arms of the system 66 directly within the wash chamber78 and/or water storage tank 82.

In the embodiment of the invention depicted in FIG. 5, the water storagetank 82 is further in fluid connection with a pump 84 in order tocontrol the flow of the treated water stored within the water storagetank 82 into the spray arms of the system 66 directly within the washchamber 78. A rinse delivery line 86 (when employing the water storagetank 82 instead of direct delivery of the treated acidic water 31 fromthe treatment reservoir 26 to deliver the treated acidic water to aspray arm, e.g. 66) may be further employed.

In an additional aspect of the invention, during the regeneration of theion exchange resin, the water storage tank 82 may be a source ofaddition for the acid regenerant 90. An acid regenerant 90 is providedinto the cleaning system 32 via an acid regenerant delivery line 88,which is in fluid communication with the water storage tank 82. At thedesignated time for regenerating the ion exchange resin within thetreatment reservoir 26 of the system, the water storage tank 82 will befilled with a combination of acid regenerant 90 and water source (eithertreated water remaining in the water storage tank or untreated water).In an aspect, an additional delivery line for providing a water sourceto the water storage tank 92 is included. This may herein be referred toas the untreated water supply delivery line 92. Thereafter, upon thewater storage tank 82 being filled with the desired concentration ofacid regenerant (diluted with a water source), the pump 84 controls theflow of the diluted acid regenerant through a diluted acid regenerantdelivery line 96 into the treatment reservoir 26 housing the ionexchange resin 28. Thereafter the regeneration of the ion exchange resin28 a waste source or effluent is produced. Such effluent may be disposedfrom the treatment reservoir 26 through a waste delivery line 94, suchas a line delivering the effluent directly to a drain within a facility.

The non-limiting embodiment of the invention shown in FIG. 5 does notdepicted all input sources or lines into the cleaning system as may bepresent. For example, the input sources for rinse aids 64 and detergentsolutions 70 are not depicted, but are understood to be included withinthe scope of the cleaning system 32 depicted in FIG. 5.

Although not depicted in the systems of FIGS. 4-5, the ware wash systemor other cleaning system can incorporate an automated tank dump and fillfor any of the fluid tanks (e.g. 26, 72). Such a feature allows for thedraining and filling, either completely or partially a volume, from thefluid tanks and therefore from the system. For example, in an embodimentof a ware wash machine, the wash tank 72 could automatically drain andfill in response to a change in the wash tank 72, such as the soiling ofthe wash tank. The use of draining and filling of the fluid tanks willfurther employ the use of valves with or without sensors.

In other embodiments not necessarily depicted in FIGS. 4-5, the treatedwater delivery line 30 may provide the treated water 31 to an additionalwater treatment apparatus 38 within the washing and/or cleaning system32. The additional water treatment apparatus 38 may include for example,a carbon filter or a reverse osmosis filter. The water that was treatedwith the additional water treatment apparatus 38 may then be connectedby an additional water delivery line 40 within the cleaning application32. One skilled in the art shall ascertain that one or more additionalwater treatment apparatuses may be employed with the water preparationsystem or apparatus 20 of the invention. In addition, the one or moreadditional water treatment apparatuses may be employed before or afterthe water source is treated according to the methods of the inventionwith the water preparation system or apparatus 20. As such, theconfiguration of the water preparation system or apparatus 20 whichtreats a water source with the ion exchange resin 28 prior to use of theadditional water treatment apparatus 38 is a non-limiting embodiment ofthe invention. In a still further alternative embodiment, no additionalwater treatment apparatuses are employed with the water preparationsystem or apparatus 20 of the invention.

In some embodiments, there is no filter between the outlet and thetreated water delivery line. In other embodiments, there is a filterbetween the outlet and the treated water delivery line. In addition, aflow control device 40 such as a valve or other mechanism forcontrolling the flow or pressure of the liquids disposed therein fortransport can be provided in the treated water delivery line 30 tocontrol the flow of the treated water 31 within the washing system. Inan alternative embodiment, the flow rate of both the water source and/ortreated water can be controlled by flow control devices.

In some embodiments, the water treatment reservoir 26 is any reservoircapable of holding the water treatment composition (e.g. ion exchangeresin) 28. The reservoir 26 can be for example, a tank, a cartridge, afilter bed of various physical shapes or sizes, or a column. In otherembodiments, the resin material may be attached or adhered to a solidsubstrate. The substrate can include, but is not limited to, aflow-through filter type pad, or paper. The substrate can also be aparticulate that can be fluidized.

The apparatuses and/or systems of the present invention can include oneor more water treatment reservoirs 26. For example, two, three or fourtreatment reservoirs containing the same or different water treatmentcompositions 28 can be used. The one or more treatment reservoirs can beprovided in any arrangement, for example, they may be provided inseries, or in parallel. In some further embodiments, the entiretreatment reservoir can be removable and replaceable. In otherembodiments, the treatment reservoir can be configured such that watertreatment composition contained within the treatment reservoir isremovable and replaceable.

The treatment reservoir may include an inlet for providing water to thetreatment reservoir and an outlet for providing treated water to adesired cleaning application, e.g., a ware wash machine. In someembodiments, the inlet is located at the top of the reservoir, and theoutlet is located at the bottom of the reservoir, such as shown in FIG.3. In alternative embodiments, the inlet is located at the bottom of thereservoir, and the outlet is located at the top of the reservoir. Thisallows for the water to flow up through the water treatment compositioncontained within the treatment reservoir. In still further embodiments,the inlet and outlet may be located at the top of the reservoir, such asshown in FIGS. 1-2. However, as one skilled in the art will ascertain,the layout and/or design of a treatment reservoir and/or the placementand orientation of the treatment reservoir within the water preparationsystem or apparatus will vary and may be customized to a particularinstitutional or industrial application for use.

In some embodiments, the treatment reservoir includes an agitated bed ofthe water treatment composition. Methods for agitating the compositioninclude, for example, flow of water through a column, by fluidization,mechanical agitation, air sparge, educator flow, baffles, flowobstructers, static mixers, high flow backwash, recirculation, andcombinations thereof. The treatment reservoir can further include a headspace above the composition contained therein, in order to allow for amore fluidized bed. In some embodiments, the resin material has adensity slightly higher than the density of water to maximizefluidization and/or agitation of the resin material.

In some embodiments, the inlet can further include a pressurized spraynozzle or educator nozzle. The spray nozzle can provide the water at anincreased force to the treatment reservoir. This increased pressurizedforce can increase the agitation of the water treatment composition andcan circulate the resin through the educator nozzle. In someembodiments, the spray nozzle provides the water to the treatmentreservoir at a rate of about 5 feet per minute to about 200 feet permin.

As disclosed herein, the treatment reservoirs housing the resinsemployed according to the invention may vary in its set-up, orientation,shape and/or size while maintaining the functionality disclosed hereinfor the treatment of water to provide a softened, acidic water source.For example, in an aspect of the invention a longer or narrower housingmay be employed for the treatment reservoirs and/or resins to maximizeor increase the contact time of the water source with the resin systems.In another aspect of the invention, the treatment reservoirs and/orresins may be shorter in length and/or wider to have a relativelyshorter contact time between the water source and the resin systemand/or to maximize flow rate and/or pressure drop within the system.According to an aspect of the invention, the shape and size of thehousing for the treatment reservoirs and/or resins is adjustable and/orcan be modified in order to balance the amount of time a water source isin contact with the cation exchange resin. As one skilled in the artshall appreciate based on the disclosure of the invention, such contacttime between the water source and the exchange resin will further impactthe characteristics of the treated acidified water source, such as theextent of acidification of the water, amount of TDS and/or extent ofremoval of hardness ions.

Additional Functional Groups

In some embodiments, an additional functional ingredient may be includedin the water preparation systems along with the water treatmentcomposition (e.g. ion exchange resin) housed within a treatmentreservoir. The additional functional ingredients can be included withinthe treatment reservoir and/or water treatment composition, or they canbe provided to the treatment reservoir from an external source, e.g., anadditional functional ingredient inlet.

Additional functional ingredients can be added directly to the watersource to be treated prior to the water source entering the treatmentapparatus. Alternatively, the additional ingredient can be added to thetreatment reservoir prior to the water source being passed through theion exchange resin.

Additional functional ingredients suitable for use with the apparatusesand/or systems of the present invention include any materials thatimpart beneficial properties to the water treatment methods, the watersource being treated, or any combination thereof. Examples of suitableadditional functional ingredients include surfactants, preferablysurfactants exhibiting wetting properties (e.g. rinse additives toincrease sheeting), sanitizing agents and/or sterilizing agents (e.g.providing sanitizing rinse), acidic detergents, enzymatic detergents andthe like.

Methods of Treating a Water Source According to the Invention

In some aspects, the present invention provides methods for controllingwater hardness and producing an acidic softened water source within acleaning application, such as a ware wash machine. Acidic softened waterhaving a hardness of less than about 2 grains and having a pH less thanabout 7, more preferably less than about 6, is produced according to themethods of the invention. Thereafter the acidic softened water can beemployed within the cleaning application.

The methods directed to controlling water hardness are also understoodto include methods for reducing scaling, buildup and/or soiling ontreated surfaces wherein the acidic softened water according to theinvention is applied within the cleaning application. In addition, themethods of the present invention are further understood to include theprotecting of equipment, e.g., industrial equipment, from the same scalebuild up and/or soiling and provide increased cleaning efficacy throughthe application of the softened acidic water to a surface in need oftreatment. Each of the same methods are also effective in reducing theuse of conventional detersive compositions as a result of the acidicsoftened water; and/or reducing the need for specific chemistries, e.g.,those containing threshold agents, chelating agents, or sequestrants, orphosphorous, in downstream cleaning processes.

The methods as disclosed herein may include contacting a water treatmentcomposition (e.g. acid regenerated resin material) with a water source,namely a hard water source. In some embodiments, the water treatmentcomposition is contained within a treatment reservoir and/or a waterpreparation system. The step of contacting can include, but is notlimited to, running the water source over or through the water treatmentcomposition (e.g. ion exchange resin). As one skilled in the art willascertain, the contact time for the water source is dependent on avariety of factors, including, for example, the pH of the water source,the hardness of the water source, and the temperature of the watersource.

A water source may be applied (i.e. water source contacted with theresin) at a variety of flow rates, as one of skill in the art can applywithout undue experimentation. For example, in preferred embodiments theflow rate through the systems of the invention is from about 0.5 toabout 50 gallons per minute. In other embodiments the flow rate is lessthan about 8 gallons per minute, less than about 40 gallons per minute,less than about 100 gallons per minute, less than about 200 gallons perminute, or from about 100 to about 1500 gallons per minute, from about160 to about 1400 gallons per minute, or about 400 to about 1200 gallonsper minute. For further example, in some embodiments, the apparatuses ofthe present invention have a flow through rate of about less than about1 cubic feet per minute, less than about 5 to about 200 cubic feet perminute, about 20 to about 175 cubic feet per minute, or about 50 toabout 150 cubic feet per minute. Without being limited according to theinvention, all flow rate ranges recited are inclusive of the numbersdefining the range and include each integer within the defined range.

For further example, a conventional ion exchange device is designed fora flow rate of about 0.3 to about 3.0 feet per minute of water velocity.This flow rate is important to allow time for the diffusion of ions tothe surface of the resin from the water for the ion exchange process tooccur. Without being limited according to the invention, all flow ratesranges recited are inclusive of the numbers defining the range andinclude each integer within the defined range.

Optionally, in some embodiments, the method includes heating the watersource prior to the step of contacting the water treatment composition(e.g. resin). Any means of heating the water source may be used with themethods and apparatuses of the present invention. In some embodiments,the water is heated to a temperature of about 30° C. to about 100° C.All temperature ranges recited are inclusive of the numbers defining therange and include each integer within the defined range.

In some aspects the water treatment according to the invention providesa cold, hard water source to a water preparation system. Aftercontacting the water source with the water treatment composition (e.g.resin) and heating, a treated, soft, acidic water is obtained and may beapplied to the various applications of use disclosed herein. Althoughnot intending to be bound to any particular theory of the invention,protons from the resin (e.g. H⁺ from the carboxylic acid group on theweak acid ion exchange resin) are exchanged with water hardness ions inthe water source to provide the treated, soft, acidic water.

Preferably the controlling of water hardness and producing an acidicsoftened water source according to the invention result in a treatedwater source having a pH less than about 7, more preferably less thanabout 6. Without being limited according to the invention, all pH rangesrecited are inclusive of the numbers defining the range and include eachinteger within the defined range.

The treated water source preferably has a water hardness less than about3, more preferably less than about 2 grains, more preferably less thanabout 1 grain, and still more preferably about 0 grains. Without beinglimited according to the invention, all ranges of water hardness recitedare inclusive of the numbers defining the range and include each integerwithin the defined range.

According to the methods of the invention the resin of the watertreatment composition may be contacted with the water source until apoint of exhaustion, viz. loaded with a plurality of multivalenthardness cations as a result of having a sufficient amount of watersource run over it. In some embodiments, the plurality of multivalentcations includes, but is not limited to, the calcium and magnesiumpresent in the water source. Without wishing to be bound by anyparticular theory, it is thought that as the water runs over the resin,the calcium and magnesium ions in the water will attach to the resin,displacing protons into the treated water source creating an acidicsoftened water.

At the point the resin is exhausted, e.g. can no longer exchange protonswith the water hardness ions of the water source, the resin isregenerated according to the methods disclosed herein. According to theinvention, the ion exchange resin is regenerated using an acid, namelyan acid regenerant. According to the invention, the acid regenerantprovides protons to the resin to restore capacity to soften and acidifywater in need of treatment according to the invention. In an aspect, theacid regenerant is a strong mineral acid or an acid salt. A preferredembodiment for regenerating the ion exchange resin uses urea sulfate asthe acid regenerant.

The contacting of the exhausted resin with the acid regenerant may befrom a few minutes to about 90 minutes, preferably from about one minuteto about 60 minutes, and more preferably from about 5 minutes to about30 minutes. Without being limited according to the invention, all rangesare inclusive of the numbers defining the range and include each integerwithin the defined range.

According to the methods of the invention, the effluent water in theregeneration step may be disposed of in a waste stream, such as depictedin FIG. 5 using for example the delivery line 94 to send a solutiongenerated from the regeneration step of the ion exchange resin to adrain or other waste stream. However, thereafter, the effluent water(e.g. treated water) in the normal service cycle is again acidicsoftened water and can be used according to the various methodsdisclosed herein.

The regeneration of the resins according to the invention may occurbased on measurements obtained from the apparatus and/or systems of theinvention. In an alternative embodiment, regeneration of the resinsaccording to the invention may occur based on the lapse of a measuredamount of time and/or volume of water treated.

Methods to Trigger Events Using the Acidic Softened Water

The methods, apparatuses and/or systems of the invention may be used fora variety of purposes. For example, the generation of the acidicsoftened water according to the invention may be used to triggerdifferent events in a water preparation system or other apparatus orsystem. In particular, the protons generated from the exchange ofhardness ions onto the resin may be monitored or measured to triggerdifferent events in the water preparation system, other apparatusesand/or systems according to the invention.

The measurements and/or monitoring according to the invention aredistinct from various commercial sensors for detecting changes and/ormeasuring water hardness in a system. For example, U.S. Pat. No.7,651,663 entitled, “Appliance Using a Water Hardness Sensor System andMethod of Operating the Same”, incorporated herein by reference in itsentirety, measures water hardness according to the amount of hardnessions (e.g. Ca²⁺, Mg²⁺) in a water source. According to the invention,the methods, apparatuses and/or systems do not measure water hardness.As opposed to these types of calorimetric or fluorescent assaysmeasuring the concentrations of ions such as calcium and magnesium, thepresent invention measures the output and/or effluent from a watertreatment system, measuring the proton released from the ion exchangeresin.

In some aspects, the monitoring or measuring of the protons is achievedby conventional pH measurements measurement of the output from the waterpreparation system or other apparatuses or systems of the invention.Sensors can be used to measure the pH as one example of a suitablemeasuring device. According to additional embodiments, the monitoring ormeasuring device to measure the pH can be employed through the use ofelectrodes, reference electrodes and/or solid state devices to sense pH.For example a pH measurement loop can be employed, such as a pH sensor,including a measuring electrode, a reference electrode and a sensor, apreamplifier and an analyzer or transmitter. Each of these are examplesof suitable measuring devices according to the invention.

In additional aspects, the pH of an incoming (e.g. non-treated) watersource containing hardness ions can be compared to the treated acidicsoftened water exiting the water preparation system, other apparatusesand/or system according to the invention. In such an embodiment, the pHdifferential can be used for a variety of purposes, including monitoringa working system. In an embodiment, the measuring of pH differentialwould detect a decrease in pH differential, triggering an applicableevent, such as regeneration of the ion exchange resin, adding detergentand/or rinse additives or other cleaning agents to be used with thetreated water. Measuring the pH differential is often useful as a resultof the variability of water hardness depending upon a water sourceemployed, as it is well known that hardness levels in influent watersare not constant. Therefore, as a result of methods of the inventionemploying the measurement of pH differential, variations in waterhardness will not be detrimental to a use application as a result of theapparatuses and/or systems being able to monitor and adjust for suchdifferential (e.g. through the triggering of various events as disclosedherein).

The regeneration of the ion exchange resins disclosed herein can betriggered by a variety of events and/or measurements as disclosedherein. In an aspect, the regeneration of the ion exchange resin may betriggered by the measurement of TDS in a system, which shall bedependent on the particular water chemistry inputted to the system. Forexample, in an aspect of the invention, the ion exchange resins removefrom about 70% to about 100% TDS from the water source. In a preferredaspect, the ion exchange resins remove from about 80% to about 100% TDS,or from about 90% to about 100% TDS from the water source. Therefore, inthe event the removal of TDS from a treated water source drops belowabout 70%, or about 80%, or about 90%, such measurement in thedifferential of the TDS between the untreated water and the treatedwater source may trigger the regeneration of the ion exchange resins.

In an additional aspect, the regeneration of the ion exchange resins maybe triggered by pH measurement of the water source and/or the treatedwater. For example, the increase in pH of a treated water source aboveabout 7 may trigger the regeneration of the ion exchange resins. Withoutbeing limited to a particular theory of the invention, the ion exchangeresin may be exhausted between a pH of about 4.9 to about 5, thereforewhen the pH of the treated water source increases to about 7, or above 7the ion exchange resin no longer contributes protons from the resin toacidify and soften the water source. Accordingly, the regeneration ofthe ion exchange resin is triggered.

One skilled in the art is knowledgeable of the various means formonitoring and/or measuring the pH according to the methods oftriggering events using the acidic softened water disclosed herein.Therefore, the scope of the invention is not limited according to themethods for monitoring and/or measuring. Conventional measuringtechniques include the use of sensors. Preferably a sensor is configuredto output a signal to a controller. The sensor may include a substrateand a sensing element disposed on the substrate. The sensing element isin contact with the flow of water in the apparatus and/or system;preferably the sensing element in contact with both the flow of incoming(e.g. non-treated) water and effluent (e.g. treated acidic softened)water.

Events triggered according to use of the apparatuses and/or systemsand/or methods according to the invention include, for example:dispensing of detergents, rinse aids and/or other cleaning compositions;varying the detergent consumption needed to wash or rinse a surfaceaccording to the methods of the invention; regeneration of the ionexchange resins; starting and/or stopping the generation of treatedwater disclosed herein, etc. The triggering of events is initiatedthrough the measurement step, thereafter communicating with a controllerto receive a signal. Thereafter, the controller works to trigger thedesired event for an apparatus and/or system according to the invention.

Methods Employing the Acidic Softened Water

The methods, apparatuses and/or systems of the invention may be used inan in-line fashion for a variety of cleaning applications to employ theacidic softened water. Thus, an apparatus of the present invention canbe used to control water hardness and/or reduce scale formation and/orenhancing cleaning efficiency and/or reduce spotting and filming causedby high TDS waters and/or reduce or eliminate use of additionalchemistry streams for cleaning (e.g. polymers, threshold agents, etc.).Unexpectedly, according to the invention, the protons in the acidicsoftened water contribute to the cleaning performance of the treatedwater source within the cleaning application.

The systems of the present invention and the methods employing the samecan be integrated into any system or appliance which uses a water sourceand is in need of water treatment, e.g., acidification and/or softeningusing a water treatment system. In particular, the systems andapparatuses of the present invention can be integrated into anyappliance or device which can provide a water source that would benefitfrom treatment using the apparatuses of the present invention, includingeither or both of acidification and/or softening.

Ware Washing Applications

In some aspects, the present disclosure includes methods of using theacidic softened water for low-temperature ware washing and sanitizing.For example, the treated acidic water is generated within an automaticwashing machine and the treated water delivery line provides deliverywithin system. The apparatus disclosed herein is incorporated into thewashing machine, such that various pumps and/or delivery lines withinthe machine are shared for one or more purposes and/or the apparatus ishoused within the washing machine. Exemplary automatic washing machinessuitable for use with the apparatuses and methods of the presentinvention include, but are not limited to, an automatic ware washingmachine, a vehicle washing system, an instrument washer, a clean inplace system, a food processing cleaning system, a bottle washer, and anautomatic laundry washing machine. Alternatively, the treated water maybe used in a manual washing system. Any automatic washing machine ormanual washing process that would benefit from the use of water treatedin accordance with the methods of the present invention can be used.

In some aspects, the present disclosure includes methods of using theacidic softened water for ware washing applications, including thosedisclosed for example in various ware washing applications using acidformulations, including U.S. Pat. Nos. 8,114,222, 8,092,613, 7,942,980,and 7,415,983, U.S. patent application Ser. Nos. 13/474,771, 13/474,765,13/474,780 and 13/112,412, including all references cited therein, whichare herein incorporated by reference in their entirety. A particularlysuitable application for use of the treated acidic water is for use inan acidic rinse cycle. For example, the treated acidic water may bedispensed with additional acidic compositions through a rinse arm,without or without an additional water rinse step, in order to lower thepH in the final rinse. In an additional application of use, the treatedacidic water may be used in an alternating fashion with alkalinedetergents and steps to improve soil removal.

In some aspects, non-limiting example of dish machines suitable forusing the systems of the invention for water conditioning and/or asource of cleaning and/or rinsing waters are disclosed, for example, inU.S. Pat. No. 9,289,107, entitled Dishmachine, the entire contents ofwhich are hereby expressly incorporated herein by reference. Furtherexamples of dish machines that may have the systems of the invention forgenerating acidic water incorporated therein includes, U.S. Pat. Nos.8,202,373, 8,092,613, 7,942,978, 7,871,521, 5,609,174, 4,826,661,4,690,305, 4,687,121, 4,426,362 and in U.S. Pat. Nos. Reissue 32,763 and32,818, the entire contents of which are hereby expressly incorporatedherein by reference. Some non-limiting examples of dish machines includedoor machines or hood machines, conveyor machines, undercountermachines, glasswashers, flight machines, pot and pan machines, utensilwashers, and consumer dish machines. The dish machines may be eithersingle tank or multi-tank machines.

A door dish machine, also called a hood dish machine, refers to acommercial dish machine wherein the soiled dishes are placed on a rackand the rack is then moved into the dish machine. Door dish machinesclean one or two racks at a time. In such machines, the rack isstationary and the wash and rinse arms move. A door machine includes twosets arms, a set of wash arms and a rinse arm, or a set of rinse arms.Door machines may be a high temperature or low temperature machine. In ahigh temperature machine the dishes are sanitized by hot water. In a lowtemperature machine the dishes are sanitized by the chemical sanitizer.The door machine may either be a recirculation machine or a dump andfill machine. In a recirculation machine, the detergent solution isreused, or “recirculated” between wash cycles. The concentration of thedetergent solution is adjusted between wash cycles so that an adequateconcentration is maintained. In a dump and fill machine, the washsolution is not reused between wash cycles. New detergent solution isadded before the next wash cycle. Some non-limiting examples of doormachines include the Ecolab Omega HT, the Hobart AM-14, the EcolabES-2000, the Hobart LT-1, the CMA EVA-200, American Dish Service L-3DWand HT-25, the Autochlor A5, the Champion D-HB, and the JacksonTempstar.

The temperature of the cleaning applications in ware wash machinesaccording to the invention may also vary depending on the dish machine,for example if the dish machine is a consumer dish machine or aninstitutional dish machine. The temperature of the cleaning solution ina consumer dish machine is typically about 110° F. (43° C.) to about150° F. (66° C.) with a rinse up to about 160° F. (71° C.). Thetemperature of the cleaning solution in a high temperature institutionaldish machine in the U.S. is about typically about 150° F. (66° C.) toabout 165° F. (74° C.) with a rinse from about 180° F. (82° C.) to about195° F. (91° C.). The temperature in a low temperature institutionaldish machine in the U.S. is typically about 120° F. (49° C.) to about140° F. (60° C.). Low temperature dish machines usually include at leasta thirty second rinse with a sanitizing solution. The temperature in ahigh temperature institutional dish machine in Asia is typically fromabout 131° F. (55° C.) to about 136° F. (58° C.) with a final rinse at180° F. (82° C.).

The disclosed methods of using the acidic softened water may also beused in a pot and pan washer, a utensil washer, glasswashers and/or aconveyor machine. A conveyor machine refers to a commercial dishmachine, wherein the soiled dishes are placed on a rack that movesthrough a dish machine on a conveyor. A conveyor machine continuouslycleans racks of soiled dishes instead of one rack at a time. Here themanifolds are typically stationary or oscillating and the rack movesthrough the machine. A conveyor machine may be a single tank ormulti-tank machine. The conveyor machine may include a prewash section.A conveyor machine may be a high temperature or low temperature machine.Finally, conveyor machines primarily recirculate the detergent solution.Some non-limiting examples of conveyor machines include the EcolabES-4400, the Jackson AJ-100, the Stero SCT-44, and the Hobart C-44, andC-66.

The incorporation of the systems of the invention into the variouscleaning applications, e.g. ware wash machines, beneficially reduces thedemands on the water treatment within a particular facility or at aparticular location. Namely, the incorporation of the water treatmentsystems into a machine ensures that only water sources used within themachine are treated, as opposed to treating all water entering aparticular facility, which may not require the treatment to generate asoftened, acidic water.

In an exemplary aspect, the methods of the invention are particularlysuitable for ware wash applications that employ at least a treated watersource according to the invention with a wash agent (e.g. detergent) forcleaning articles within the particular machine employed. In an aspect,at least one cleaning product or wash agent is applied to the articlesduring a wash phase of the cleaning application. The wash agent istypically a cleaning agent formed by dissolving one or more chemicalproducts in water within the wash tank of the system. The term chemicalproduct is used broadly to encompass, without limitation, any type ofdetergent, soap or any other product used for cleaning and/orsanitizing.

In an aspect of the invention, the particular cleaning application intowhich the water treatment reservoir is incorporated, includes at leastan inlet for providing a water source; a water treatment reservoir,wherein the inlet is in fluid communication with the water treatmentreservoir; a water treatment component housed within the water treatmentreservoir, wherein said water treatment component comprises at least oneion exchange resin capable of generating a treated water source byexchanging protons on said resin for water hardness ions in said watersource, and wherein said ion exchange resin is an acid form or in aninert metal form; an outlet, wherein the outlet is in fluidcommunication with the water treatment reservoir; a chamber into whicharticles are placed for cleaning; a treated water delivery line in fluidcommunication between the outlet and the chamber; a wash tank, whereinthe wash tank is in fluid communication with a dispensing module thatdispenses a wash agent into the wash tank; a wash agent delivery line influid communication with the wash tank and the chamber; and an aciddelivery line in fluid communication with the water treatment reservoir,wherein an acid regenerant is delivered to the water treatment reservoirfor regenerating the ion exchange resin. The system may also include anadditional water treatment apparatus and water delivery line in fluidconnection with the water treatment reservoir. Still further, the systemmay also include a measuring device for obtaining pH and/or protonconcentration measurements from the water treatment reservoir, the watersource and/or the treated water source, and a controller to receive themeasurements and trigger an event.

In still further aspects of the invention, the particular cleaningapplication into which the water treatment reservoir is incorporated mayalso include at least one pump configured to pump the treated watersource, the wash agent and/or additional cleaning and/or rinsing agentsinto the chamber. Still further aspects of the system may include abooster heater for heating the treated water source, the wash agentcontained in a wash tank, a rinse agent and/or additional cleaningagents to at least a predetermined temperature. In addition, additionaldelivery pumps and lines may be included in a particular cleaning systemfor the delivery of additional chemical products (e.g. rinse aids,sanitizing agents, etc.). It is to be understood that such additionalcomponents of particular cleaning systems may similarly be excluded. Forexample, in an embodiment of the invention a cleaning system 32 does notrequire the use of a booster heater 76.

The methods of the invention are not limited with respect to theparticular sequence of cleaning, rinsing and/or sanitizing steps. Forexample, the cleaning method may include at least one wash phase duringwhich a wash agent is dispensed into the wash chamber. The wash agentmay be formed in a wash tank from a combination of at least one chemicalproduct and water, which thereafter is suitable for use in looseningsoils on the treated articles and sanitizing the articles in the washchamber. In addition, at least one rinse agent may be applied to thearticles within the chamber during one or more rinse phases. The rinseagents dispensed into the wash chamber during any number of rinse phaseswash off any soil and wash agent residue remaining on the articles aftera wash phase. The rinse agent is typically water with one or morewetting and/or sanitizing agents. In aspects of the invention, the wateremployed in the rinse phases may be the treated water source generatedfrom the ion exchange resins of the invention.

It is understood that the various systems may further employ one or moresumps for collecting wash agents, rinse agents and/or other chemicalproducts dispensed into the chamber during the steps of the cleaningprocess disclosed herein. These may include, for example, a wash sumpand/or a rinse sump. In other aspects, a single sump may be employed bya system.

The various cleaning phases and/or rinse phases may be repeated anynumber of times, occur at various temperatures and/or spans of time,which shall not limit the scope of the claimed invention. For example,the length of time during which each of the washing and/or rinsingphases occur within the cleaning process may be dependent on manyfactors, such as, without limitation, targeted sanitation level,targeted water usage, targeted energy usage and the expected soil levelon the articles being cleaned by the machine.

Laundry and Other Applications

In additional aspects, the present disclosure includes methods ofincorporating the systems of the invention into laundry machines inorder to use the acidic softened water for laundry applications. Forexample, the acidic treated water can be generated and used in anautomatic textile washing machine at the pre-treatment, washing,souring, softening, and/or rinsing stages.

In a particular embodiment, the present invention may be incorporatedinto a washing machine in a variety of ways. In some embodiments, thetreatment reservoir may be used to supply treated water within a washingsystem and/or to a rinsing system of a laundry washing machine. In someembodiments, the treatment reservoir may be used to supply a mixture oftreated water and detergent within a laundry washing system.

In still additional aspects, the present disclosure includes methods ofusing the acidic softened water in a variety of additional industrialand domestic applications. The water treatment methods and apparatusescan be employed in a residential setting or in a commercial setting,e.g., in a restaurant, hotel, hospital. In addition to the ware washing(e.g., washing eating and cooking utensils and dishes) and laundryapplications, for example, a water treatment method, system, orapparatus of the present invention can be used in: vehicle careapplications, e.g., to treat water used for pre-rinsing, e.g., analkaline presoak and/or low pH presoak, washing, polishing, and rinsinga vehicle; industrial applications, e.g., cooling towers, boilers,industrial equipment including heat exchangers; clean-in-place systems(CIP) and clean-out-of-place systems (COP); and other applicationswherein the systems of the invention can be incorporated to providein-line treated acidified water, including those disclosed in co-pendingapplication Ser. No. 13/711,843, now issued as U.S. Pat. No. 9,463,455,entitled Acid Regeneration of Ion Exchange Resins for IndustrialApplications, the entire contents of which is herein incorporated byreference.

In additional aspects, use of a treated acidic water source according tothe invention reduces or eliminates use of additional chemistry streamswithin a particular cleaning application (e.g. polymers, thresholdagents, etc.). Preferably, use of a treated acidic water sourceaccording to the invention allows for the use of specificenvironmentally friendly detersive compositions, e.g., thosesubstantially free of or free of builders, chelants, sequestrants and/orphosphorous.

The various methods of use employing the acidic softened water accordingto the invention may be used in combination with any detersivecompositions. For example, a cleaning composition, a rinse agentcomposition and/or a drying agent composition can be combined withtreated water to form a use solution. The articles to be cleaned and/orrinsed are then contacted with the use solution. Exemplary detergentcompositions include ware washing detergent compositions, laundrydetergent compositions, CIP detergent compositions, environmentalcleaning compositions, hard surface cleaning compositions (such as thosefor use on counters or floors), motor vehicle washing compositions, andglass cleaning compositions. Exemplary rinse agent compositions includethose compositions used to reduce streaking or filming on a surface suchas glass. Exemplary drying agent compositions include dewateringcompositions. In the vehicle washing industry, it is often desirable toinclude a dewatering step where a sheeting or beading agent is appliedto the vehicle exterior.

However, according to a preferred embodiment the use of the treatedacidic water reduces and/or eliminates the need for additional cleaningcompositions (e.g. polymers, threshold agents, etc.) and/or reduces theoverall detergent consumption due to the increased cleaning efficacy ofthe treated water. Therefore, in some embodiments, the detersivecomposition for use with the methods of the present invention includes adetergent that is substantially free of a chelant, builder, sequestrant,and/or threshold agent, e.g., an aminocarboxylic acid, a condensedphosphate, a phosphonate, a polyacrylate, or the like. Without wishingto be bound by any particular theory, it is thought that because themethods and apparatus of the present invention reduce the negativeeffects of hardness ions in the water source, when used with adetergent, there is a substantially reduced or eliminated need toinclude chelating agents, builders, sequestrants, or threshold agents inthe detergent composition in order to handle the hardness ions.

For example, use of a water source treated in accordance with themethods of the present invention increases the efficacy of conventionaldetergents. It is known that hardness ions combine with soap anddetergents to form a scale or scum. Further, hardness ions limit theamount of lather formed with soaps and detergents. Without wishing to bebound by any particular theory, it is thought that by reducing theamount of these hardness ions the amount of these detrimental sideeffects can be reduced.

In some embodiments of use, there is a substantial reduction in thedetergent consumption as a result of the use of the treated acidic watersource for the cleaning application, including for example, at least a5% detergent consumption reduction, at least a 10% detergent consumptionreduction, at least a 20% detergent consumption reduction, or at least a25-30% detergent consumption reduction. Without being limited accordingto the invention, all percentages of detergent consumption reductionranges recited are inclusive of the numbers defining the range andinclude each integer within the defined range.

As one skilled in the art will ascertain, in some embodiments, thedetersive composition may include other additives, includingconventional additives such as bleaching agents, hardening agents orsolubility modifiers, defoamers, anti-redeposition agents, thresholdagents, stabilizers, dispersants, enzymes, surfactants, aestheticenhancing agents (i.e., dye, perfume), and the like. Adjuvants and otheradditive ingredients will vary according to the type of compositionbeing manufactured. It should be understood that these additives areoptional and need not be included in the cleaning composition. When theyare included, they can be included in an amount that provides for theeffectiveness of the particular type of component.

Those skilled in the art will recognize, or be able to ascertain usingno more than routine experimentation, numerous equivalents to thespecific procedures, embodiments, claims, and examples described herein.Such equivalents are considered to be within the scope of this inventionand covered by the claims appended hereto. The contents of allreferences, patents, and patent applications cited throughout thisapplication are hereby incorporated by reference. The invention isfurther illustrated by the following examples, which should not beconstrued as further limiting.

All publications and patent applications in this specification areindicative of the level of ordinary skill in the art to which thisinvention pertains. All publications and patent applications are hereinincorporated by reference to the same extent as if each individualpublication or patent application was specifically and individuallyindicated by reference.

EXAMPLES

Embodiments of the present invention are further defined in thefollowing non-limiting Examples. It should be understood that theseExamples, while indicating certain embodiments of the invention, aregiven by way of illustration only. From the above discussion and theseExamples, one skilled in the art can ascertain the essentialcharacteristics of this invention, and without departing from the spiritand scope thereof, can make various changes and modifications of theembodiments of the invention to adapt it to various usages andconditions. Thus, various modifications of the embodiments of theinvention, in addition to those shown and described herein, will beapparent to those skilled in the art from the foregoing description.Such modifications are also intended to fall within the scope of theappended claims.

Example 1

Previous experiments show that ware washing results will be improvedusing softened water by conventional means and acidified by consumabledetergents and/or rinse additives. When conventional ion exchange resinsare exhausted, the water is no longer softened and brine is typicallyused to regenerate the resin. The water that is no longer softened oftencauses poor washing results unless additional detergents concentrationcontaining builders, chelants or polymers are increased and additionalrinse additive is used.

An experiment showing the proof of scale build up on ware was conductedusing a carbonate 500 ppm, 75 cycle test. Table 1 quantifies the resultsof ware treated according to the experiment, wherein Glasses 1A weretreated using only hard water (17 Grain/Gal hardness water) and Glasses1B were treated using the acidic softened water according to theinvention. The resultant scale build up on the treated ware surfaceswere depicted by photograph and measured visually according to thegrading scale (below).

The 75 cycle test employed was performed using six 10 oz. Libbey glassesand four plastic tumblers (SAN=Styrene Acrylonitrile) on a Hobart AM-14ware wash machine and 17 grain water (1 grain=17 ppm). Thespecifications of the Hobart AM-14 ware wash machine include: Washbathvolume: 60 L; Rinse volume: 4.5 L; Wash time: 40 sec.; Rinse time: 9sec.

Initially the glasses were cleaned according to procedures ensuringremoval of all film and foreign material from the glass surface. The 75cycle test was initiated. After the completion of each cycle, themachine is appropriately dosed (automatically) to maintain the initialconcentration. Glasses and tumbles dry overnight and then are graded forfilm accumulation using a strong light source. (1—No film; 2—Trace film;3—Light film; 4—Medium film; 5—Heavy film). As shown in Table 1, Glasses1A (hard water—17 grain) were graded a level 5, demonstrating heavyfilm. The glasses treated according to the invention shown in Glasses 1B(acidic softened water) were graded a level 1, demonstrating no film.

TABLE 1 Evaluated Glasses 1A 1B Film Accumulation 5 1

Example 2

An experiment showing the proof of protein removal on ware was conductedusing the detergent APEXNC 1000 ppm (Ecolab®) and the 7 cycles proteinremoval test. Table 2 show the results of ware treated according to theexperiment, wherein Glasses 2A were treated using only hard water (5Grain/Gal hardness water) and Glasses 2B were treated using the acidicsoftened water according to the invention. The resultant scale build upon the treated ware surfaces are depicted by photograph and measuredvisually according to the grading scale (below).

The 7 cycle protein test employed was performed to provide a genericmethod for evaluating glass filming, spotting, and soil removal in aninstitutional dish machine. Clean test glasses are washed in aninstitutional dish machine. The performance of the detergent or rinseaid is measured by the prevention of water spotting or filming and theremoval of soil from plastic tumblers and Libbey Glass tumblers.According to this experimentation the performance of use of softenedacid water (as opposed to 5 grain hard water) were evaluated.

Clean Libbey glasses were used for each test product and new plastictumblers were used for each experiment. Food soils were prepared foodsoils. The dish machine was filled with the tested water sources(described according to Glasses 2A-2B) and heaters were turned on. Thefinal rinse temperature was adjusted to 180° F. for the high temperaturemachines. Glasses and plastic tumblers were soiled and placed in theoven at 160° F. for 8 minutes. While glasses were drying, the ware washmachine was primed with 120 g of soil previously prepared (correspondingto 2000 ppm of food soil in the sump). Soiled glasses/plastic tumblersare placed in the rack beside the re-deposition glasses/plastictumblers. The wash machine is started and glasses are run through anautomatic cycle. When the cycle has ended, the top of the glasses aremopped with a dry towel. The soiling procedure is repeated. At thebeginning of each cycle, the appropriate amount of detergent and foodsoil are added to the wash tank to make up for the rinse dilution. Thesteps are repeated until seven cycles are complete.

Results were evaluated using the de-staining methods employing aCoomassie Blue R Stain solution to evaluate glasses visually against awhile background. Glasses are first stained using the Coomassie Blue RStain solution and rinsed thoroughly with de-staining solution (methanoland acetic acid in distilled water). Each glass is then visually ratedin a viewing area against a white background, wherein residual proteinremains stained blue. (1—No protein; 2—20% of glass surface covered inprotein; 3—40% of glass surface covered in protein; 4—60% of glasssurface covered in protein; 5—greater than 80% of glass surface coveredin protein As shown in Table 2 the Glasses 2A (hard water—5 grain) weregraded a level 2, demonstrating 20% of glass surface covered in protein.The glasses treated according to the invention shown in Glasses 2B(acidic softened water) were graded a level 1, demonstrating no proteinon the glasses.

TABLE 2 Evaluated Glasses 2A 2B Film Accumulation 2 1

Example 3

The capacity of a commercially-available weak acid resin against pH ofwater was tested. An Amberlite® IRC 76 ion exchange resin(commercially-available from Rohm and Haas Company) was tested.Amberlite® IRC 76 ion exchange resin is one example of acommercially-available weak acidic resin having a polyacrylic copolymerwith carboxylic acid functional group. This particular resin ischaracterized by a volume variation smaller than conventional weak acidresins and can be used in H⁺, Na⁺ or NH₄ ⁺ forms and can also be used toremove bicarbonate hardness from water. The resin is known to besensitive to chlorine in water (affecting the lifetime and performanceof the resin). The operating capacity of the resin is a function ofanalysis, temperature and service flow rate of water. The resin isreadily regenerated with little over stoichiometric amounts of strongacids.

On average, the use of a conventional weak acid resin used in ionexchange water softening applications are designed for bed depths of 2.6feet for water treatment rates of about 2 to about 20 gallons perminute. However, one skilled in the art may vary the water treatmentrates, including for example from about 0.5 to about 50 gallons perminute.

The configuration used for the testing of the capacity of the ionexchange resin used a flow rate of about 5-10 gallons of water perminute and consumed less than 1 cubic foot of resin for the system. Inaddition, various monitoring devices were in use within the system tomeasure flow, water hardness (e.g. hardness ions measured by titrationmethod), pressure within the system (e.g. measurement of presumerequired for effective

e rinsing, preferably pressure measurement of about 20 psi), pH of theeffluent (e.g. electrode measurement), and TDS (e.g. ICP analyticalmethod for TDS).

FIG. 6 shows a diagram of the capacity of an acid regenerated ionexchange resin v. pH of treated water according to an embodiment of theinvention. The best results are obtained from the resin with a pH lessthan about 6. Preferably the pH is less than about 7.

Example 4

The capacity of a commercially available weak acid resin againsthardness of water was tested. An Amberlite® IRC 76 ion exchange resin(commercially-available from Rohm and Haas Company) was tested.Amberlite® IRC 76 ion exchange resin is one example of acommercially-available weak acidic resin having a polyacrylic copolymerwith carboxylic acid functional group. This particular resin ischaracterized by a volume variation smaller than conventional weak acidresins and can be used in H⁺, Na⁺ or NH₄ ⁺ forms and can also be used toremove bicarbonate hardness from water. The resin is known to besensitive to chlorine in water (affecting the lifetime and performanceof the resin). The operating capacity of the resin is a function ofanalysis, temperature and service flow rate of water. The resin isreadily regenerated with little over stoichiometric amounts of strongacids.

The configuration used for the testing of the capacity of the ionexchange resin used a flow rate of about 5-10 gallons of water perminute and consumed less than 1 cubic foot of resin for the system. Inaddition, various monitoring devices were in use within the system tomeasure flow, water hardness (e.g. hardness ions measured by titrationmethod), pressure within the system (e.g. measurement of presumerequired for effective rinsing, preferably pressure measurement of about20 psi), pH of the effluent (e.g. electrode measurement), and TDS (e.g.ICP analytical method for TDS).

FIG. 7 shows a diagram of the capacity of an acid regenerated ionexchange resin v. water hardness of treated water according to anembodiment of the invention. The best results are obtained from theresin system with water hardness less than about 2 grains.

Example 5

Layered resin bed systems were evaluated to assess the impact on treatedwater hardness using more than one acid cation exchange resin. 4710grams of the Dowex® MAC-3 weak cation exchange resins(commercially-available from Dow Chemical Company) were used to form alayered bed using two of the weak acid cation exchange resins, such asshown in FIG. 3A. The Dowex® MAC-3 LB resin is one example of acommercially-available weak acidic resin having carboxylic acidfunctional groups. The MAC-3 WAC resins were packed into two connected19 inch by 5 inch diameter housing tubes. 3575 grams of the Dowex® MAC-3weak cation exchange resin (commercially-available from Dow ChemicalCompany) and 1235 grams of Dowex® Marathon-C (H form) strong cationexchange resin (commercially-available from Dow Chemical Company) wereused to form a mixed layered bed, such as shown in FIG. 3B. The cationexchange resins were packed into two connected 19 inch by 5 inchdiameter housing tubes.

Hard water (17 grains) was provided to the layered resin bed systemsdepicted in FIGS. 3A-3B at a controlled rate of about 0.8 gallons perminute. The water from the outlet of the second treatment reservoir wasmeasured for both hardness and pH. Water samples were taken to test pHlevels against capacity.

FIG. 8 shows a diagram of the capacity of the layered bed systems. Asshown, the layered weak acid regenerated ion exchange resin providedsoftened water having between about 0.5 to 1 grains, whereas the layeredmixed bed of weak acid regenerated ion exchange resin and a strong acidregenerated ion exchange resin provided softened water having 0 grainhardness. The use of the layered mixed bed employing the strong acidcation exchange resin provided greater reduction in water hardness,despite its overall lower capacity for reducing water hardness if usedalone. However, the water softened using the layered weak acidregenerated ion exchange resins provided the additional benefit ofproviding reduced pH softened water, which provides additional cleaningbenefits.

As shown in the figure, each of the layered beds demonstrated softeningefficacies sustained for at least about 150 gallons of treated water.Thereafter between about 150 gallons to 200 gallons the resins becameexhausted and were unable to continue to sufficiently remove waterhardness. According to aspects of the invention, for the evaluated watertreatment apparatuses in this Example, the use of acid regenerationwould need to be employed after about 150 gallons of treated water.

FIG. 9 shows a diagram of the pH versus the capacity of the layered bedsystems. As shown, the layered weak acid ion exchange resin bed (i.e.employing a single type of resin) resulted in less acidified treatedwater source as the capacity of the system was tested. Namely, aboveabout 200 gallons of treated water, the pH of the single resin layeredbed began to increase above about 4, whereas the layered mix resin bedsystem maintained a constant acidified water having a pH between about 3to about 3.5.

Example 6

The use of an acid regenerant according to embodiments of the inventionwas analyzed. A single weak acid resin bed, such as disclosed in Example4 was regenerated using various acid regenerants disclosed herein. Itwas found that the regeneration process is initially dominated bythermodynamics. A regenerant with a sufficiently low pH will drive theprocess over the energy barrier, showing a fast pH drop at the firstseveral minutes. Thereafter, the regeneration process is controlled bykinetics. This requires a regenerant to be used for a sufficient amountof time (e.g. about 5 to about 90 minutes) to drive the regeneration ofthe resin to completion.

As shown in FIGS. 10A-B the use of a strong acid regenerant (HCL 0.38M(FIG. 10A), HCL 1.8M (FIG. 10B)) is required to sufficiently decreasethe pH in the weak acid resin. According to embodiments of the inventionthe concentration of the acid regenerant used in the regeneration cyclewill depend upon the molarity of the acid employed. In some embodiments,the concentration of the acid used in a solution for providing the acidregenerant to the ion exchange resin is from about 1% to about 20%, fromabout 2% to about 10%, or about 10% for regeneration.

After the resin has been regenerated, as shown in FIGS. 10A-B, anexemplary service cycle (i.e. treating hard water with the acidregenerated resin) can be used to again provide an treated acidifiedwater source. As shown in FIG. 11, the use of the strong acid regenerantof FIG. 10B provides superior treatment capacity for a longer servicecycle.

Example 7

The use of additional acid regenerants was evaluated pursuant to theresults of Example 6. The following acid regenerants were employed andreported in equivalence of the various acids employed: 1.2 eq sulfuricacid, 1.2 eq urea sulfate, 1.2 eq hydrochloric acid, 1.2 eq MSA, and 1.4eq citric acid. FIG. 12 shows the drop in pH of the resin during aregeneration step employing the various acid regenerants. Beneficially,the use of equivalence of the various acids employed in this exampletakes into account the various fluctuating factors, including forexample, the size of the system, amount of hardness to be removed, etc.

After the resin has been regenerated, as shown in FIG. 12, an exemplaryservice cycle (i.e. treating hard water with the acid regenerated resin)was employed to determine the efficacy of service cycles, as measured bywater hardness of the treated water source, based on the use of thevarious acid regenerants. As shown in FIG. 13, the service cycle ofvarious acid regenerant provided treated acidic water having a hardnessof about 1 or less than about 1 for at least 100 gallons of treatedwater.

The inventions being thus described, it will be obvious that the samemay be varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the inventions and all suchmodifications are intended to be included within the scope of thefollowing claims.

What is claimed:
 1. An integrated system employing an ion exchange resinregenerated by an acid for producing an acidic softened water sourcecomprising: an inlet for providing a water source; a water treatmentreservoir, wherein the inlet is in fluid communication with the watertreatment reservoir; a water treatment component housed within the watertreatment reservoir, wherein said water treatment component comprises atleast one ion exchange resin capable of generating a treated watersource by exchanging protons on said resin for dissolved cationsincluding water hardness ions and total dissolved solids in said watersource, and wherein said ion exchange resin is an acid form or in aninert metal form; an outlet, wherein the outlet is in fluidcommunication with the water treatment reservoir; a chamber into whicharticles are placed for cleaning; a treated water delivery line in fluidcommunication between the outlet and the chamber; a wash tank, whereinthe wash tank is in fluid communication with a dispensing module thatdispenses a wash agent into the wash tank; a wash agent delivery line influid communication with the wash tank and the chamber; an acid deliveryline in fluid communication with the water treatment reservoir, whereinan acid regenerant is delivered to the water treatment reservoir forregenerating the ion exchange resin; an acid regenerant storagereservoir in fluid communication with the acid delivery line; an acidregenerant contained in the acid regenerant storage reservoir; a pumpconfigured to pump the acid regenerant into the water treatmentreservoir; wherein the treated water source is a softened, acidic, andlow total dissolved solids (TDS) water having a hardness level of lessthan about 2 grains and a pH less than about
 6. 2. The system accordingto claim 1, wherein said ion exchange resin is a weak acid cationexchange resin and/or a strong acid cation exchange resin.
 3. The systemaccording to claim 1, wherein said ion exchange resin is a weak acidexchange resin having a polyacrylic copolymer matrix and carboxylic acidfunctional group or is a strong acid exchange resin having a polystyrenematrix and sulfonic acid functional group.
 4. The system according toclaim 1, wherein said ion exchange resin is an acid exchange resinselected from the group consisting of a cross-linked acrylic acid withcarboxylic acid functional group, a cross-linked methacrylic acid withcarboxylic acid functional group, a polystyrene with sulfonic acidfunctional group, and mixtures of thereof.
 5. The system according toclaim 1, further comprising an additional water treatment apparatus andwater delivery line in fluid connection with the water treatmentreservoir.
 6. The system according to claim 1, further comprising ameasuring device for obtaining pH and/or proton concentration and/ortotal dissolved solids measurements from the water treatment reservoir,the water source and/or the treated water source, and a controller toreceive the measurements and trigger an event.
 7. The system accordingto claim 1, further comprising at least one pump configured to pump thetreated water source, the wash agent and/or additional cleaning and/orrinsing agents into the chamber.
 8. The system according to claim 1,further comprising a booster heater for heating the treated watersource, the wash agent contained in a wash tank, a rinse agent and/oradditional cleaning agents to at least a predetermined temperature. 9.The system according to claim 1, wherein the wash agent is combined withwater and/or additional chemical products in the wash tank.
 10. Thesystem according to claim 1, wherein a dilution system is in fluidcommunication with said treated water delivery line that is fluidlyconnected with said outlet from said water treatment reservoir, whereinsaid treated water delivery line delivers said treated water to saiddilution system before entering said chamber.
 11. The system accordingto claim 1, further comprising a water storage tank in fluidcommunication with said treated water delivery line, and a pump in fluidcommunication with said water storage tank and said wash tank, whereinsaid water storage tank is a reservoir for holding treated water source.12. The system according to claim 1, wherein the pump controls deliveryof a dilute acid regenerant.
 13. The system according to claim 12,further comprising a waste delivery line in fluid communication withsaid water treatment reservoir, wherein said waste delivery line removesan effluent waste source from the regeneration of the ion exchangeresin.
 14. The system according to claim 12, further comprising anuntreated water delivery line in fluid communication with said aciddelivery line and/or said acid regenerant storage reservoir to provide awater source to form a dilute acid regeneration source for regenerationof the ion exchange resin.